Electrical actuating means fob



May 21, 1935. G. P. ."owLEs 209K433 ELECTRICAL ACTUATING MEANS FOR CLOCKS AND INSTRUMENTS Filed Dec. 18, 1929 31/ 47 @wwamio z,

Patented May 1935 ELECTRICAL ACTUATING MEANS FOR (BLOCKS AND INSTRUMENTS George P. Cowles, Waterbury, Conn. Application December 18, 1929, Serial No. 414,940

particularly to an electrically-operated alarm clock.

The invention herein disclosed is an improve' ment over the invention covered in a previous Patent #1334341, granted November 5, 1929, to the same inventor.

An object of the invention is to provide an electrically actuated instrument of the above nature which is operated entirely on closed circuit and is adapted to drive a plurality of mechanisms from the same source of potential energy, and which instrument will be simple in construction, inexpensive to manufacture, easy to install and manipulate, compact, and very eflicient and durable in use.

With these and other objects in view there have been illustrated on the accompanying drawing a form in which the invention may be conveniently embodied in practice.

Fig. 1 represents a rear view or the electrically actuated alarm clock with the back cover removed.

Fig. 2 is a side elevation oi! the same, shown partly in section, and with the casing, bell, and vibratory armature removed for greater cleamess.

Referring now to the drawing in which like reference numerals denote corresponding parts throughout the several views, the numeral II indicates a rotary armature, preferably of the nonself-starting, synchronous type, and the numeral I l indicates a laterally-vibrating armature for operating the alarm. Both of said armatures I 0 and II receive alternating magnetic flux from a joint field flowing through a core I2 of any suitable magnetic material, such as laminated iron. The core I2 is energized by a coil I3, through which flows an alternating current of substantially constant frequency, said current being supplied through a lead-in conductor cord l4 connected to any suitable source 01' single-phase alternating current, such as a house-lighting circuit.

Vibratory armature The core I2 is secured ,on a back movement plate I5 by means of screws I6, and is so shaped as to include within its magnetic influence the energizing coil I3, the rotary armature l0, andthe vibratory armature II. The vibratory armature I I is carried by a leaf-spring II which may also be of magnetic material and be included within the magnetic circuit. The spring I1 is fastened to the field core I2, as by means of screws l8, and to the armature I I, as. by means of rivets I9.

In order to limit the motion of the vibratory armature H away from the field core H2 in response to the tension of the spring ll, provision is made or an adjustable stop screw 20 mounted on an upstanding lug 2! on the back movement plate I5. The vibratory armature H is prevented from entirely closing the magnetic circuit, when periodically attracted toward the field core I2 by means of an armature knob 4! which engages a bell 22 attached by a screw 23 to a supporting post 24 mounted on the plate I5.

- In order to provide a stop for the armature II when the bell 22 is removed, provision is made 01' a set-screw 24a supported on the back movement plate I5 in alinement with the set-screw 20. For the purpose of normally holding the vibratory armature II out of operation until the time has arrived to give the alarm, provision is made of a resilient angular cam spring 25 having a finger 25a interposed between the core I2 and the armature II, said cam spring 25 being rigidly secured at its'base to the front movement plate 34, as clearly shown on Fig. 2.

Rotary armature The rotary armature I0 is mounted within a cylindrical housing 25 held between a pair of pole portions of the core I2, said housing being held in position, as by a clamp 21. The armature ID has a pinion 21a rotatable therewith for driving a gear 28 also located within the housing 26, which contains a quantity or thin oil or other lubricant.

The rotary armature I0 is preferably made of any construction capable oi being revolved synchronously by an alternating field, but it will be understood that it may also be made non-synchronous within the general spirit and scope of the invention. In the latter case, a suitable main spring, winding-stop mechanism, and mechanical escapement would oi. course be included as a part of the timing movement.

Starting mechanism In order to manually start the rotary armature I 0, provision is made of a manually rotatable staff 29 passing through the back movement plate I5 and having a pinion 29a fastened thereto within the movement formeshing with a time train 33 to be hereinafter described. By means of this construction the rotary armature I0 may be started by manually rotating the staff 29 until said armature has been brought up to synchronous speed. after which it will continue to rotate automatically.

In order to permit the alarm to be set for any speed for driving the hour and minute hands from the armature Ill, provision is made of a gear train-33 positioned between the back movement plate l5 and the front movement plate 34, said plates [5 and 34 being separated by means of suitable pillars 35 and 36. The gear train 33 drives the hour and minute hands 3m and 31b and also an alarm dial train comprising gears 31 and 38. The pointer 33a is secured on the forward end 39 of the alarm set-staff 30, as by staking, and an alarm cam 40 is loosely journaled on said stall, said cam 40 being rigidly secured to the gear 33.

It is to be understood that the term "time-indicating mechanism as hereinafter used includes the gear train 33 as well as the hour and minute hands 3m and 3H; and the dial train.

Operation In operation, when it is desired to start the clock, the conductor cord M will first be plugged into an A. C. line and current will then fiow through the coil I3, creating alternating lines of force for energizing the field core l2 with a pulsating magnetic fiux in synchronism with the frequency of the alternations of the line. The fiux which passes through the upper arms of the core l2 energizes the rotary armature III in such a manner that when the starting stafi 29 is manually rotated to the proper synchonous speed, said armature will then continue to rotate automatically in synchronism with the frequency of the line current. The gear train 33 and the hour and minute hands 3| :1 and 3lb will then be driven at practically uniform speed as long as the electric circuit remains closed.

The magnetic flux which passes through the lower arms of the core l2 energizes the vibratory armature l I and the magnetic conducting spring l1, causing the armature II to vibrate when the cam spring finger 25a has been withdrawn. The hammer knob 4| on the end of the armature II will then successively strike the bell 22 until shut off.

In order to shut ofl the alarm the stafi 33 may be manually rotated until the cam spring finger 25a again passes between the armature II and core l2 for preventing further motion of said armature. It will be understood, of course, that the alarm-striking armature H may also be silenced, if desired, by an auxiliary mechanical shut-d switch, not shown, located on the casing 32, said construction being well-known in the art.

It will thus be seen that the flux in the field core is common to both the rotary armature l0 and the vibratory armature I l and will energize both of them so long as current flows through the coil [3. Moreover, since there are no open circuits mer knob M will be prevented from striking the bell 22 until the cam 40 has been again revolved to the position shown in Fig. 2 by the gear 38 driven by the time train 33.

aooassa At this time, a pin 63 on the alarm staff 33 will be underpassed by the peak of the cam 13 causing a slot 33 in the cam 53 to engage said pin 52. The gear 33 and cam 33 will then suddenly slide forward under the action of the resilient cam spring 25. The finger 25a will thus be retracted from the vibratory armature ll, releasing the latter, which will then be free to respond to the pulsating energy received from the magnetic field core H2. The armature M will then vibrate at approximately synchronous speed-about 120 motions per second when operating on a 60 cycle line.

The rotary armature i3 is mounted on a pinion shaft I2, between a pair of plates I3 and I4. In order to mechanically absorb the inherent vibrations due to the pulsating flux, the shaft 12 has securely mounted thereon a disc '55 of any suitable material of high density, such as lead. By means of this construction, the unpleasant hum which would otherwise be produced is avoided.

The plates I3 and M are spaced apart by means of pillars 16. A time-trainoperating stafl' 11 is carried by a bushing 18, soldered or otherwise secured to the housing 26, and projecting through the back-movement frame IS. The stafi 11 carries a pinion 19 for driving the time train 33.

One advantage of the present invention is the eliminationof the mechanical escapement, main spring, main arbor, intermediate time wheel,

alarm spring, alarm arbor, and alarm escapement,

and attendant troublesome mechanism common! employed in alarm clocks.

From the foregoing it will be seen that there has been herein disclosed an electrically-operated instrument which is not only practical and efilcient and economical of electrical energy, but which may be constructed from a small number of parts. Moreover, the armatures employed are independent of each other and operated by a joint magnetic field.

It is to be'clearly understood that the invention is not limited to the specific forms of armatures herein disclosed, but broadly covers various other types of rotary and vibratory armatures.

. While there have been disclosed in this specification several forms in which the invention may be embodied, it is to be understood that these forms are shown for the purpose of illustration only, and that the invention is not to be limited to the specific disclosures but may be modified and embodied in various other forms without departing from its spirit. In short, the invention includes all the modifications and embodiments coming within the scope of the following claims.

Having thus fully described the invention, what is claimed as new, and for which it is desired to secure Letters Patent, is:

1. In combination with clock mechanism and alarm device comprising coacting sound producing elements connected with the opposite ends of the motor core, and setting means for the alarm device including a detent and means for moving the same in one direction to engage the detent between said coactingmembers to prevent operation of the alarm device, and spring means acting to move said detent in the opposite direction at a predetermined time in the operation of the clock mechanism to permit operation of the alarm device.

2. In combination with clock mechanism and the adjacent end of said core to prevent operation of the alarm, and means operatively connected to said clock mechanism and adapted to release said detent at a predetermined time in the operation of the clock mechanism to permit operation of the alarm.

GEORGE P. COWLES. 

